Traot-stopkng device



C. W. MARDEN.

TRAIN STOPPING DEVICE.

APPLICAHON man MAR. 13. 1920.

Patented May 16, 1922;

UNITED STATES TRAIN STOPIE'ING' DEVICE.

Specificationof Letters Patent.

Patented May 16,1922.

Application filed March 13, 1920. Serial no. 365,594.

T 0 all whom it may concern:

Be it known that I, CHARLES W. MARDEN, a citizen of the United States, residing at Portsmouth, in the county of Rockingham and State of New Hampshire, have invented a new and useful Train-Stopping Device, of which the following is a specification.

- This invention relates to a train-stopping device designed for operation by a semaphore signal when the latter is set in danger position.

It is the object of my invention to provide a device which will automatically stop a train if an attempt is made to run past a danger signal.

WVith this object in view, an important feature of my invention relates to the provision of means for quickly opening an air outlet in the brake system and for holding the same open until the device is manually reset.

Another feature relates to the provision of a balanced valve at the air outlet, by which easy operation of the device is facilitated.

I also provide a contact arm of such shape that easy and gradual movement of the parts when engaged by a semaphore signal is insured.

Further features of my invention relate to arrangements and combinations of parts hereinafter described and more particularly pointed out in the appended claims.

A preferred form of my invention is shown in the drawings, in which Fig. 1 is a front elevation of parts of my improved mechanism, showing the relation of the same to a semaphore signal;

Fig. 2 is a side elevation of the parts shown in Fig. 1;

Fig. 3 is a plan view of the contact arm; and

Fig. 4 is a sectional elevation of the valve controlling the air outlet.

Referring to the drawings, I have indicated a semaphore signal 10 of usual form, mounted on a pole 11 beside the track, and movable from the safety position shown in dottedlines to the danger position shown in full lines.

A contact arm 12 is secured to the end of a shaft 13, extending transversely of a locomotive cab or other structure 14. The shaft 13 is supported in bearings 15 and is provided with an arm 16 (Fig. 2), connected by a link 17 to a valve stem 18 projecting from a valve 19 indicated diagrammatically in Figs. 1 and 2, and shown in section in Fig. 41.

The contact arm 12 is formed as an inverted V in cross section and is kite-shaped in plan, as appears in Fig. 3. The rear portion of the arm is convex upwardly to insure easy motion to the parts operated by said arm. The side walls of the arm are preferably perforated to reduce air resistance.

The valve 19 is mounted on an outlet pipe 20 connected in the brake system, and in cludes balanced valves 21 and 22 movable by the valve stem 18. The valve 21 is slightly smaller than the valve 22 and the pressure in the pipe 20 is exerted to open the valve 21 and to close the valve, 22.

A cone-shaped collar 23 is fixed on the valve stem 18 and a spring latch 24 is positioned for outward movement as the valve is opened. The latch then advances to a position beneath the collar 23 to hold the valve in raised or open position. The latch 24: may be manually withdrawn by a handle 25 to reset the mechanism; A spring 26 seats the valves 21 and 22 firmly when the latch 2% is withdrawn and maintains the arm 12 in operative position.

The operation of my improved trainstopping device will be apparent from inspection of the drawings. When the arm 12 is engaged by a semaphore in danger position, the curved rear end of the arm will be depressed and at the same time, the arm 16 and link 17 will be raised, causing corres ponding movement of the valve stem 18 and the valves 21 and 22. This movement is against the pressure of the spring 26 and the differential pressure on the valves 21 and 22.

The valves will be maintained in raised or open position by the spring latch 24. The

pipe 20 will then allow the escape of air from the brake system, setting the train brakes. After the train is stopped, the latch 24L may be withdrawn, restoring the parts to their original positions.

It will be understood that the form and position of the arm 12 may be varied to correspond to the location of the semaphore signals, and that the shaft may be extended across the locomotive and may be provided with a second contact arm 12 on the opposite end of the shaft 18 when so desired.

Having thus described my invention, it

will be evident that changes and modifications can be made therein by those skilled in the art within the spirit and scope of my invention as set forth in the claims, and I do not Wish to be otherwise limited to the de tails herein disclosed, but What I claim is 1. In a train stopping device, a contact arm actuated by a semaphore signal in danger position, said arm being substantially kite-shaped in plan and having a convex edge engaging said semaphore signal.

2. In a train-stopping device, a contact arm actuated by a semaphore signal in danger position, said arm being of inverted V-shape in vertical section and being convex along its upper edge to insure easy engagement With the semaphore signal.

In testimony whereof I have hereunto afiixed my signature.

CHARLES l/V. MARDEN. 

